Why does H265 not support resolutions higher than 4k?

The actual maximum allowed resolution for H265 is 8192×4320, why can’t I export H265 encoded videos with resolutions higher than 4k?

8192×4320 as you mentioned as maximum export resolution, is 8K DCI, slightly wider aspect ratio then 8K TVs, (256:135 / 1.8962 / 17:9), used in movie projection.

8K UHD has the standard 16:9 aspect ratio used by the majority of modern TVs and computer monitors, and has 7680 x 4320 pixels (1.78 / 16:9). This is the highest resolution defined in the Rec. 2020 (UHDTV) standard.

While this name “8K” is commonly used as a catch-all term, it’s actually broken down into two main sub-categories: 8K UHD (Ultra-High Definition) and 8K DCI (Digital Cinema Initiatives), a partnership between a number of major movie studios that was formed to establish standards for digital cinema systems (https://www.dcimovies.com/)

The reason for the difference is simple: by making movies in a wider aspect ratio, people still have a reason to go to the cinema…
While modern 16:9 TVs are wide, the differentiation remains, enabling cinemas to provide a more immersive widescreen experience.

In any case those resolutions are much higher then 4k, it is in the 8k spectrum, you can export in 8K with H.265, you are not limited to 4K.

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Of course it’s limited, look:
image

It should allow to export the output video, which is 7680x4320. Horizontally it reaches the limit, but vertically it doesn’t.

PS: FFmpeg allows me to encode at resolutions higher than 4k with H265, so I have to assume that this is a technical limitation of the programme which I don’t understand. Other AI video post-processing software I use allows export of 8k videos with H265.

Does anyone have anything to say about this? I don’t like having to resort to ProRes to export videos at a higher resolution of 3840x2560p, I wish I could do it with HEVC.

try this:

  1. goto C:\ProgramData\Topaz Labs LLC\Topaz Video AI\models\
  2. edit encoders.json
  3. try changing those values for the codec you using (and the OS you using - most codecs have both entries for Windows and macOS, be sure you edit the one that is your OS) and see if it works.

image

I don’t have that file on that folder.

them i think you should reinstall your app as this is essential file for TVAI to function correctly.
or maybe it is “hidden” file.

As a matter of fact, the actual limit is not the aspect ratio but the amount of total pixels the codec has been programmed to support up to 8192×4320 = 35389440 pixels

So 35389440 pixels are the total pixels allowed by HEVC.

So i.e. the ratio 9612 x 3681 is allowed (= 35395066px)

You can choose your favorite pixel ratio if the total amount of pixels is not exceeded.